Our goals in this 5-year project in response to PAR-05-026, Community Participation in Research, are to acquire crucially needed evidence to support interventions promoting infants'mental health in foster care, while building community capacity to deliver infant mental health interventions and services to foster families. The specific aims are: 1. to collaborate with Pierce County, Washington multi-system partners by continuing a process of formative research and stakeholder participation, to modify existing relationship and attachment-based interventions for implementation with infants in foster care and their caregivers. 2. To work with community partners to establish the necessary research infrastructure to conduct a comparative effectiveness study (CES) measuring the effectiveness of the agreed upon intervention. 3. To conduct a CES to test the effectiveness of the agreed upon intervention on the following outcomes: foster caregiver sensitivity, infant attachment security and emotional, behavioral, and developmental functioning, and placement stability. 4. To examine qualitative and quantitative research findings related to Aims 1-3 with community partners in order to plan system-wide next steps to promote social-emotional well-being and relationship stability for infants and young children in the child welfare system. The proposed research is a community-based longitudinal comparative effectiveness study. Foster families (N=210) will be enrolled over the course of 27 months when their infants are 7 months old. The foster families will be randomly assigned to experimental and comparison conditions involving two different prevention programs. The experimental group will receive an attachment theory based program;the comparison group will receive early education support services. Both groups will receive a pretest prior to random assignment and 12-, 18-, and 24-month assessments of caregiver sensitive caregiving, parenting stress, and commitment to this infant;and infant emotional and behavioral regulation, attachment security, and developmental status. Placement and child welfare data will be obtained from the state child welfare data base. A process evaluation will be conducted of the collaborative partnership.